(1) Field of the Invention
The present invention relates to a recovery vehicle having a 360.degree. rotatable hoist unit and a towing unit which are mounted onto a vehicle frame having a single axle. In particular, the invention relates to a recovery vehicle wherein the 360.degree. rotatable hoist is able to be rotated completely behind the cab of the vehicle with the entire hoist unit spaced above the vehicle frame. The recovery vehicle has stabilizing means adjacent to the front and rear of each side of the axle which act to both anchor and stabilize the vehicle frame during lifting.
(2) Prior Art
The prior art has shown various types of recovery vehicles and recovery units which mount on vehicles some of which are rotatable 360 degrees. Illustrative are U.S. Pat. Nos. 2,787,383 to Antos et al.; 2,911,111 to Grove; 4,134,500 to Sauber; 4,515,282 to Falch; 4,790,710 to Ayalon; 5,064,078 to Van Staveren.
Antos et al describes a rotatable hydraulic crane having a stationary support mounted on the rear of a vehicle between the dual axles and wheels. The vehicle is provided with outriggers and adjustable jacks to give the vehicle greater stability while using the boom crane to swing a load from one side of the vehicle to the other.
Grove describes a mobile crane having a telescopic sectionalized boom which allows loading and unloading and operates without winches. The crane is rotatably mounted onto the chassis of a mobile unit. The telescopic boom is provided with hydraulic cylinders which control the extension and retraction of the boom.
Sauber describes a mobile derrick, aerial man lifts and the like having a boom pivotably mounted on a clevis frame mounted for rotation on a turntable. The turntable is carried on a pedestal secured to the frame of a vehicle.
Falch describes a rescue vehicle having a rotatable crane mounted on a dual rear axle frame wherein a rescue winch is mounted on the crane turret for providing horizontal pulling power.
Van Staveren describes a combination portable hoist, crane and automobile towing mechanism. The device is mounted onto a modified vehicle bumper of a typical automobile. The crane is able to rotate 360.degree. in order to load and unload objects onto the vehicle.
Ayalon describes a multi-purpose recovery vehicle which includes a wheel mounted chassis, a continuously skewing crane assembly and a recovery assembly. The recovery assembly includes an extensible and retractable towing assembly, a retractable anchor assembly, a retractable stabilizing assembly and a winch. The recovery assembly is mounted rearward of and adjacent to the rear wall of the bed of the recovery. vehicle. The skewing crane is mounted onto the chassis of the recovery vehicle which is preferably a conventional three axle heavy duty truck.
The U.S. Pat. Des. Nos. 205,030 to Grove; 205,031 to Grove; and 301,127 to Lindblom; show various designs for recovery units and recovery vehicles.
None of the above references describe a recovery vehicle wherein the hoist unit is rotatable 360.degree. such that the entire hoist unit is able to be positioned over the vehicle frame behind the cab of the recovery vehicle. Further, the references do not describe a single axle recovery vehicle having the ability to lift 32,000 lbs wherein the hoist unit is mounted over the single rear axle. Finally, none of the references show the use of the stabilizer means which can act as an anchor during lifting.